Electronic devices rely on various user movements as input to perform different functions and to operate in various modes or states. For examples, user gestures such as hand movements can be detected and translated into user control of a menu item or a game function. Similar to gestures, eye movements can be detected to perform scroll operation, to keep a screen turned on, or to operate a head-up-display.
Eye tracking is the technique of measuring a point of a person's gaze, i.e., where the person's eyes are looking at, or following the movement of the point of gaze. Eye tracking devices and systems can detect and measure eye positions and eye movement. Eye tracking technology has been used clinically to help people with disabilities, in research on the visual system, in medical and cognitive studies, as well as in psychology, in cognitive linguistics and in product design.